The resignation of Donald Rumsfeld as United States defence secretary in the aftermath of heavy Republican losses in the mid-term elections on 7 November 2006 is an event whose reverberations will be felt far beyond Washington. His likely replacement Robert Gates will (subject to confirmation hearings) bring a different track record and style, and draw on longstanding experience in the national-security apparatus - including in relation to Iran.

But if the political atmosphere in Washington has been transformed by the Democrats' victory and Rumsfeld's departure, the underlying strategic realities in Iraq and in the "long war" are as intractable as ever. In this respect, new information about an under-reported incident in Saudi Arabia casts an interesting sidelight on where US policy - and al-Qaida's operations - may be heading.

The success of failure

Nearly nine months ago, on 24 February 2006, there was an attack on an oil processing plant at Abqaiq in Saudi Arabia. The initial news reports of the incident were quickly matched by announcements from the controlling Saudi Aramco company that little damage had been done and that all the security measures in place had worked. Only one bulletin at this early stage (on Al-Arabiya TV) spoke of a major incident, involving an explosion that had rocked the facility and set off a fire.

This in turn was countered by a statement from the Saudi minister of petroleum and mineral resources, Ali bin Ibrahim Al-Naimi, who announced that Saudi security forces and Saudi Aramco employees had "forestalled a terrorist attempt" that "resulted in a minor fire which was immediately extinguished, and...no changes in the production levels of oil or gas in Saudi Arabia" (see PennEnergy, Oil and Gas News, 24 February 2006). Other official sources spoke of two car-bombers failing to penetrate the outer-security perimeter and into any significant part of the complex.

Paul Rogers is professor of peace studies at Bradford University, northern England. He has been writing a weekly column on global security on openDemocracy since 26 September 2001

In addition to his weekly openDemocracy column, Paul Rogers writes an international security monthly briefing for the Oxford Research Group; for details, click here

Paul Rogers's new book is Into the Long War: Oxford Research Group, International Security Report 2006 (Pluto Press, November 2006)

A collection of Paul Rogers's Oxford Research Group briefings, Iraq and the War on Terror: Twelve Months of Insurgency, 2004-05 is published by IB Tauris (October 2005)

An earlier article in this series suggested that this was far from the end of the matter (see "Abqaiq's warning", 2 March 2006). The article pointed out that although there had been previous paramilitary attacks on offices and residential compounds maintained by oil companies operating in Saudi Arabia, this was the first major attempt to attack a production complex itself.

Moreover, Abqaiq is not just any facility: it is the largest oil-processing plant in the world. It is situated to the northeast of some of the largest Saudi fields (including the huge Ghawar field), and processes around two-thirds of all Saudi oil; from it, the oil is pumped onto tank farms and refineries at the Ras Tanura terminal - itself the world's biggest - where it is loaded into tankers and exported.

"A website used by al-Qaida quickly hosted a claim of responsibility for the attack by one of the movement's affiliates. The posting named the two ‘martyrs' killed, announced that the operation followed an earlier pledge from Osama bin Laden to destroy such targets, and warned of further attacks. This latest incident was ‘part of the project to rid the Arabian peninsula of the infidels' and was intended to stop the "pillage of oil wealth" from Muslims."

One effect of the attack was to increase oil-market jitters, pushing up the price of oil by $2 a barrel. But the limited media coverage reflected the instant narrative of the event: that the Saudi forces had been engaged in a tough, and rapidly successful security operation against paramilitary radicals. As a result, Abqaiq was assigned - in public, at least - to the category of forlorn attempts by al-Qaida to gain publicity for a losing cause.

The military fallout

The matter might have rested there but for two unexpected developments: the recent, sudden interest by the United States navy in the security of Saudi oil-export facilities, and information from several reliable sources that the Abqaiq attack was much more serious than either Saudi Aramco or the Saudi government has admitted.

The Saudi decision to allow ships of the US fifth fleet to guard the Ras Tanura export terminal is certainly unexpected and not without risk. One of the key motivating factors for the al-Qaida movement in the 1990s was the presence of US forces in Saudi Arabia ("the kingdom of the two holy places") after the 1991 Iraq war. Among the many consequences were a number of attacks on US military personnel, including the massive truck bomb that devastated the Khobar Towers barracks-block at the Dhahran air base in June 1996, killing nineteen US service personnel and injuring 500.

Most of the US forces then relocated to a new secure air base south of Riyadh, well away from centres of population; but that too was abandoned two years ago, leaving Saudi Arabia without any US combat troops. Even the fifth fleet is headquartered in neighbouring Bahrain, thus removing the presence of al-Qaida's "far enemy" from the kingdom.

The new deployment at Ras Tanura - even if it is a naval presence rather than ground troops stationed on the kingdom's soil - reverses this trend. It also has a wider value to the Bush administration as it tries to gain greater support form Arab states in the western Gulf in its ongoing confrontation with Iran (see Riad Kahwaji & Barbara Opall-Rome, "U.S. Seeks Arab Allies Against Iran", Defense News, 16 October 2006 [subscription only]).

For their part, the Saudis are clearly taking a risk, though it seems that concern over the security of their oil facilities has overcome the nervousness over offering provocation (and a propaganda gift) to al-Qaida. It is in this context that what actually happened at Abqaiq is so interesting.

Three vehicles were used, two of them containing large bombs and the third in support. After an exchange of fire with guards, all three broke through the south gates at the plant. The first truck-bomber, apparently disorientated, still managed to get right inside the plant and detonate the explosives in a parking-lot. The blast blew open a crater over a metre deep and six metres wide, and scattered shrapnel and debris for hundreds of metres, damaging equipment (though not affecting key functions) in the process.

The second bomber succeeded in getting close to the centre of the plant, where he detonated the explosives near a key set of pipeline junctions. A building was destroyed and a fire started, but the impact fell short of damaging the pipeline junctions themselves.

As it was, everything was repaired at an indecent speed (in marked contrast to the normal pace of life at the plant), allowing the company to purvey its reassuring narrative. Since the attack, security has been strengthened, with a range of additional barriers, more armed guards and perimeter lighting.

Al-Qaida's trial run

It is still fair to say that the Abqaiq attack failed. It is also now apparent that, far from being a botched attempt that did not even penetrate the complex, the assault came very much closer to having a devastating impact. The implications are considerable.

Two-thirds of Saudi Arabia's entire oil production goes through the single plant at Abqaiq, which thus processes one-sixth of total world oil production. This alone makes it an extraordinarily attractive target for paramilitary groups. The adjacent Ras Tanura export operation is similarly vital in economic and political terms. This reality is sufficient to explain the Saudi willingness to accept US military assistance.

For the United States, the near-success of the Abqaiq attack is actually something of a bonus, in two ways. First, it allows the US military to become involved once more in Saudi Arabia, and at the very time when the fallout of the Iraq war is enforcing a rethinking at senior levels about long-term military strategy in the region (see "After failure in Iraq", 26 October 2006). Second, at a time of tension with Iran it creates an opportunity for the US to send a reminder to Tehran of the extent of the US presence across the Gulf.

For the al-Qaida movement, meanwhile, Abqaiq may have been little more than a trial run. Almost nine months later, amid a period of heightened concern over possible attacks in Britain or the United States, it may well be that the movement is planning quite different operations, and that Gulf oil facilities are high on its list.